The emerald ash borer, a small beetle from Asia that is blamed for the destruction of 20 million trees in Michigan, has made its way to Maryland.
Testing by the state Department of Agriculture last week detected beetle-infested ash trees in Prince George's County between Clinton and Brandywine.
The state imposed a quarantine that prohibits moving ash trees, logs, fallen banches, stumps or roots in or out of Prince George's County until further notice.
The quarantine also bans transporting of ash firewood or any hardwood firewood - including oak, maple and cherry - in or out of the county.
Anyone violating the quarantine could be fined up to $500.
Letters were sent n Wednesday to 195 plant dealers in the county informing them of the quarantine.
Although the beetle has been found in only about a dozen trees, Mary Ellen Setting, assistant state agriculture secretary in the office of pest management, said that it "could be very serious. In Michigan the beetle killed or forced the destruction of 20 million ash trees."
Ash trees are popular with landscape architects, she said. Nearly 300,000 have been planted in Baltimore and about 6 million in the metropolitan area.
The U.S. Department of Agriculture estimates that damage to trees in the Baltimore region could exceed $227 million if the ash borer becomes established.
Setting said the beetle damages only ash trees.
State officials suspect that the current infestation stems from a shipment of 121 ash trees to a Prince George's County nursery in 2003. The trees were shipped in violation of a quarantine in Michigan.
At that time, the state cut down and burned all ash trees within half a mile of the infestation site, south of Andrews Air Force Base.
After destroying about 500 trees, the Agriculture Department planted about 100 of what Setting called "sentinel ash trees" throughout Maryland.
"They serve as bait," she said to attract any beetle in the area.
Annual testing of those trees had detected no signs of the beetle until last week.
Setting said the beetles were found in a test tree in the burn area and in other trees outside the area.
"While we are disappointed to find the emerald ash borer after nearly three years of no detection, we are pleased that our surveillance efforts have proven to be effective and that we found the insect before it could spread further," said Agriculture Secretary Lewis R. Riley.
The state has begun measures to control and eradicate the pest, he said.
Over the next two months, workers from the state Agriculture and Natural Resources departments will survey the area to find all ash trees. The results of the survey will determine the course of action and the scope of tree destruction and pest surveillance.
Setting said the usual practice is to cut and burn all ash trees in defined areas.
She said state officials will concentrate on a diamond-shaped area of Prince George's County bordered roughly by Surratts Road, Brandywine Road and U.S. 301 (Crain Highway).
Letters explaining the actions will be sent to about 5,800 area homeowners.
C. Ronald Franks, secretary of the Maryland Department of Natural Resources, said the quarantine is designed to safeguard trees on private and public lands, as well as the nursery industry.
Ash trees are one of the most common landscaping trees in the nation and are common in Western Maryland forests. The wood has a variety of applications, including baseball bats, floors and cabinets.
Setting said that because the beetle is on the federal quarantine list the USDA will help pay for eradication efforts.
The emerald ash borer burrows through the bark of ash trees and halts the flow of water from the roots to the branches. Leaves begin to yellow and branches in the top third of the tree die first. The tree usually dies within two or three years.
The beetle usually leaves a D-shaped hole in the bark, and shoots begin to grow from the base of the tree.
Setting said those who suspect an infestation in their trees should contact the home and garden center at University of Maryland Cooperative Extension office in their county. She said a hot line would be established.
She described the beetle as "a shiny emerald green" about a half-inch long and a sixteenth of an inch wide.
The beetle is believed to have made its way from Asia to Michigan in 2002 on wooden packaging materials carried on cargo planes. It has also been detected in Indiana, Illinois and Ohio.
An infestation of bark beetle at the Broad Creek Boys Scout camp in Harford County last summer prompted the destruction of about 8,500 white pines scattered over 12 acres off Castleton Road near Dublin.